Specifications

18
• Connect a lightening surge absorber, as shown in the diagram, to deal with power surges.
• Be sure to create an exclusive ground for the power cord’s FG terminal. Check that the
grounding resistance is less than 100 Ω.
• Inside the PL unit, the SG (Signal Ground) and FG (Frame Ground) terminals are connected.
When connecting an external device to the PL using the SG terminal, be sure to check that
no short-circuit loop is created when you setup the system.
• The grounding wire should have a cross sectional area greater than 2mm
2
[0.0062inch
2
].
Create the connection point as close to the PL unit as possible, and make the wire as short, as
possible. When using a long grounding wire, replace the thin wire with a thicker wire, and
place it in a duct.
• Input and output signal lines must be separated from the power control cables for operating
circuits.
• If this is not possible, use a shielded cable and connect the shield to the PL unit’s frame.
• To improve noise immunity, it is recommended to attach a ferrite core to the power cord.
• Be sure to ground the surge absorber (E1) separately from the PL unit
(E2).
• Select a surge absorber that has a maximum circuit voltage greater than
that of the peak voltage of the power supply.
3 Grounding Cautions
4 Input/Output Signal Line Cautions
PL Unit
FG
E2
Lightening Surge Absorber
Other
Equipment
Exclusive Grounding
(BEST)
Common Grounding
(OK)
PL
Unit
PL
Unit
Other
Equipment
Common Grounding
(Not OK)
PL
Unit
Other
Equipment